Sound-reproducing machine



an. IVA,

Sept. 16 1924.

WITNE SS 1,508,681 L. F. DOUGLASS SOUND REPRODUCING MACHINE OriginalFiled April 24, 1916 2 Sheets-Sheet 1 INVENTOR A TTORN E Y;

Sept. 16, 1924. 1,508,681

L. F. DOUGLASS SOUND REPRODUCING MACHINE Original Filed April 24, 1916 2Sheets-Sheet 2 INVENTOR zeaizFflolg/aag y A T TQRN E Y5 "ran STATESPATENT OFFICE.

H F. DOUGLASS, OF SAN RAFAEL, CALIFORNIA, ASSIGNOR '10 VICTOR TALKING-MACHINE COMPANY. A CORPORATION OF NEW JERSEY.

- SOUND-REPRODUCING MACHINE.

Application filed April 24, 1918, Serial No. 93,275. Renewed April 27,1922. serial No. 557,085.

To all whom it may concern:

Be it knownthat I, LEON F. DOUGLABS, a citizen of the United States,residing at San Rafael, county of Marin, and State of means to receiveand amplify the sound waves created thereby and discharge them. to theatmosphere, and my inv'entedimprovements have for their primary objectthe utilization of. such sound waves to cause 1 variations correspondingto sound waves in an electric circuit and transform said vibrations insaid electric circuit back into secondary sound vibrations, whereby theprimary vibrations (produced by such diaphragm are cause reproduction ofrecorded sound vibrations and through amplifying passages as desired;and additionally whereby the secondary vibrations may be varied, that isto say, the volume of the sound ultimately delivered can be made greateror less, as desired. Both sets of vibrations are rovidedfor by mechanismwhich isenclosed within a single cabinet so that the manipulation of thesecondary vibrations for the urpose of enhancin the primary vibrationsis readily control ed.

To these ends my invention, while it does.

not broadly comprehend the reception upon a telephone circuit, of thesound vibra-1 tions emanating from a talking machine, as that is notnew, it involves that basic principle, exemplified in mechanism socombining, in a novel manner, the diaphragm holder or sound box of asound reproducing machine, its tone arm, and, if deslred, its horn orother mechanical am l'ifier of sound waves, with telephonic recelvin anddischarging apparatus, whereby eac or ,all of the desired results, abovestated, are produced. The term secondary reproduction, in the sense inwhich I use it, means the electrically-created sound pulsations of thediaphragm of the telephone apparatus, as distinguished from thediaphragm of the to produce a secondary sound box of the talking machinewhich produces the sound waves constituting what I refer to as theprimary vibrations.

The defect in the known method and means of exemplifying the basicprinciple referred to, is largely due to connecting the telephonecircuit directly to the stylus of the diaphragm holder forming part ofthe usual sound box of the talkin machine or to the diaphragm thereof,wh1ch results in weighing the stylus or diaphragm, or otherwisedecreasing the effectiveness of such diaphragm, by noticeably lesseningthe volume of the sound produced thereby and he quently varyingits toneand timbre. This defect is entirely overcome in my device wherein thedia hra is free from such connection and t e e ectiveness of the maryvibrations is retained, the resultant secondary vibrations conveyed torelatively distant points, and wherein moreover the secondary vibrationsare or may be augmented in yolume by the means hereinafter described. a

In the. accompanyin "drawings illustrating the best form in w ich I haveembodied my invention: i

Figure 1 is a vertical section, part1 in elevation, through the verticalcenter 0 the apparatus shown mounted in a'duplex containmg casing;

Fi 2 is a plan view, partly in section,

of'a own form of tone arm construction, with sound box. or diaphragmholder, and showing the telephone transmitter and circuit connectionsmounted upon the articulated extremity of the tone arm roper;

Fig. 3 is a central section, part y in elevaprition, of the receiver ofa telephonic apparatus mounted dependingly on the inlet-end of davertically disposed amplifying device; an

Fig. 4'is a section on line 44 of Fig. 2 of a perforated plug throughwhich primary sound vibrations pass from the tone arm of the machine tothe transmitter of the telephone circuit.

Referring now to said drawings, 1 and 21 indicate, respectively, the twomembers of a duplex containing cabinet, of which 1 is of known form andcharacter, w thin which are operative] mounted, in a known way, thehorizontal y swinging tone arm 3 of a sound reproducing apparatus. witha known character of sound box or diaphragm and stylus holder 2 mountedon the free end of the tone arm; a rotatable record holder 23 and amotor 24 to operate it. Extending downwardly through a lower chamber inthe cabi: net member 1 is a tubular conduit 25 operatively connectedwith the open swivelled end of the tone arm 3, and serving as a passageway and conduit for the primary sound vibrations created by thediaphragm of the sound box 2.

Rearward of the cabinet member 1 is mounted a second cabinet. member 21,with coinciding apertures 26 and 27 between the contiguous'walls of thetwo cabinet members. Through the lower of these apertures,

26, extends the aforesaid sound wave conduit 25 which, when it entersthe cabinet member 21 is reversely curved to extend upwardly as at 25for a short distance, preferably in conical formation, and thereaftermay extenddntegrally to the open top of the cabinet member, operating inthe usual manner as an amplifying tube or horn, or it may supportmounted therein, as shown in Fig. 1, a conical or flaring rectangularamplifying chamber 21*, containing, if desired, one or a series ofpartitioning and vertically disposed sounding boards 21". A hinged lid22 may be supplied for the supplemental cabinet. member 21, or for both.A duplicate amplifying chamber 20 or its equivalent referred to, is alsomounted in the cabinet member 21, the basal or inlet end of the member20 being operatively connected to the larger end of a preferably taperedsound tube 20 mounted on standards 20"; the lower end of the sound tube20 supporting the connected discharge end of ,a telephone receiver 17containing the usual diaphragm 24 and operating mechanism. At the rearof the cabinet member 21 is a door 30 whereby easy access to theenclosed parts is provlded.

The receiver 17 as shown in Fig. 3, consists of an outer casing 18 whichhas screwed upon the upper end a cap 32 so formed as to receive thecasing 18 by a screw joint or similar connection. The 0 ap is formedwith an opening at the top, and is spaced from the diaphragm 24. Thevertical tapered sound tube 20 isformed to closely contact with the capand by means of bolts 29 disposed about the edges of the sound tube thecap is fastened thereto and maintains the casing 17 and connected partsin position. Within the space between the cap 32 and the casing 17 aninner casing 19 is disposed which contains within'itself the end of themagnet 'well known in such receivers. The diaphragm and the outer end ofthe magnet are disposed so that the diaphragm ordinarily does notcontact with the end of the magnet. The peripheral portions of thediaphragm are closely seated upon the contacting portions of the casing19. To avoid the detrimental effect of working the diawith openings sothat no air pocketshall' be below the diaphragm. Four of such open:

ings are shown in the drawings and are denoted by 18 which are in theouter casing and 19 which are in the. inner casing. By this constructionI have made it possible for the diaphragm 24 to act against equalresistance on each of its sides, namely, that of the atmosphere.

The casing 17 except as referred to above has the re lar form used intelephone receivers an has attached'thereto' thewires 17 which conveythe current to and from the magnet to function the diaphragm when theimpulses are present in the circuit.

The circuit which conducts the impulses to the receiver 17 and itsdiaphragm 24 consists of wiring and apparatus as follows:

The wires 17 run to the induction. coil 14 of usual fabrication. A, wire17* leads from said coil 14 to several cells 15 convenientl locatedinthe bottom of the cabinet mem r 21 as sources'of electric energy, anda wire 17 c connects the coil 14 tothe transmitter 13 later described indetail. From the transmitter 13 the wire 17 leads to the resistanceswitch 16 and thence to the battery 15. This switch possesses thecharacteristics of resistance switches as now used where the position ofthe swinging member thereof varies the amount of resistance interposedin the circuit and thus with the variation of the position of theswinging member the effective amount of current in the circuit may bealtered as desired.

In Fig. 2 are shown the transmitter 13 and its connections to and withthe tone sound record. At 9 there is a screw connection between portion5 of t e goose neck 4 which is of cylindrical formation and fits withinthe outer sleeve 6 on the end of the tone arm pro er 3, which is atright angles thereto. At is formed an enlargement or shoulder upon thegooseneck 4. The plug 8, outside 0 the inner sleeve 5, is also providedwith a shoulder 10, similar to the shoulder 7, both being of the sameexterior diameter as the outer sleeve 6. By reason of the two shouldersat each end of the inner sleeve 5 the gooseneck and the parts carriedthereby inlug 8 and the inner sleeve cluding the sound box oscillate invertical planes to and from the sound record 31.

In Fig. 4, is shown a section through the plug 8, taken on the plane 44of Fig. 2. On the outside is seen the sleeve 6, next the sleeve 5 ofgooseneck 4, and at the inside the lug 8 with six apertures 12therethrough. 'ome of the' sound waves passing through the gooseneck 4to tone arm proper 3 will pass through the a ertures 12 and impinge uponand actuate t e diaphragm 28 of the transmitter 13.

The apertures 12 are so arranged and are of such size and number, as tosoften or reduce the intensity of the vibrations received from theconduits whereby such vibrations may act with modifiediorce best suitedto the limits of mot-ion of a microphone diaphragm such as 28 in atelephonic circuit.

By the construction and arrangement of parts above set forth the soundvibrations oft-he reproduced soundsare transmitted to the diaphragm 28and to the telephonic circuit leading to the receiver 17 withoutafi'ecting or modifying in the sli htest manner the normally free actionoft e diaphragm or stylus bar of the sound box 2.

The 0 ration of the device is as folloygz A soun record 31 is placedupon the tu table 23 of the motor mechanism and the turntable caused torotate; i-the sound box 2 with stylus positioned therein is placed uponthe record and the recorded sounds are 1 thereby reproduced andconducted throu h the conduit 4 to the tone arm 3, through t e k soundconduit member 25 to the continuation 25 thereof and to the amplifier21. After amplification the reproduced sound may pass to the atmosphereas usual. The apparatus described is of course a well known form ofsound re reducing apparatus and has to do with t 0 development of theprimary vibrations. I

The secondary vibrations are those which result from the transmission ofthe aforesaid primary sound waves from the conduit 4, through the lug 8to the microphone diaphragm 28 o? the transmitter 13. The switch 16 ismanually thrown to close the electric circuit whenever it is desired toen plement the primary vibrations with t e secondary vibrations.

With current in the telephonic circuit the vibration of the diaphragm 28of the micro hone-13ers transformed throu h the action of the microphoneinto imp s in the electric circuit which are transmitted to the ma etofthe receiver 17.

Throu the action of the magnet 33and the diap ragm 24 in 17 the electricim s are again changed the sound vibra ons which, proceeding from theupper side of the diap ragm 24 pass to the tapered sound conduit 20 andfrom thence to the amplifier 2th The co-acting amplifier adjacent tionor oudness is alone desired.

mvention, however, a double volume of re-' to amplifier 20 is seen to becapable of transmitting vibrations similar to the amplifier 20 and thesevibrations of the amplifiers which are enclosed in the same cabinet passtherefrom to the atmosphere.

By varying the current strength throu h the switch control the amplitudeof t e secondary vibrations is or may be modified and of course by thebreaking of the circuit by the switch the production of secondary soundvibrations may be entirely stopped.

By suitably manipulating the apparatus to produce or not producesecondary vibrations in conjunction with the primary vibrations of soundat least three desirable and advantageous results are produced; thefirst of which is that by cutting out the secondary vibrations a talkingmachine may be operated in the usual manner; secondly, whenthe'apparatus is to be used for a larger room or when greater volume isessentlal, the introduction of the secondary vibrations, in conjunctionwith the primary vibrations, supplies the needed volume with a ran e ofregulation such as ma adapt the mac ine, first used essentially orreproduction in a small space, to one capable of filling a large roomand capable of being heard over extraneous noises such as those producedby the motion of dancers and by conversation;

and thirdly, the advantage of having both simultaneously from bothamplifiers to a" listener. appears to him to be but one sound comingfrom one source and having pleas- .ing and desirable qualities or proerties-all of which cannot be obtained by t e use of either type ofamplifier alone. This is so on account of the following reasons: Thesecondary sound vibrations produced by the telephonic circuit have tonalcharacteristics which are eculiar thereto and quite different from t oseof the mechanically reproduced sounds; and it has been observed that asthe volume of such electrically produced sound is increased thesepeculiar characteristics are augmented and emphasized so that alone andin great volume telephonically produced sounds may be objectionable froman artistic standpoint although entirely satisfacto when merelyincreased enetraith my produced sound may be easily obtained withoutforcing either kind of amplification and without making it necessa toemphasize or exaggerate the undesirab e characteristics of eit er t peof amplification, so that the loud am lilied sound produced by my aparatus, a ove described, will have init a l the pleasing qualities ofboth types of sound amplification, free from those undesirable qualitiesusuall present in the reproduction of sound 0 great volume *Having thusdescribed my invention, I

'. phragm of the transmitter'is actuated by diaphragm is actuated solelsaid primary vibrations on their passage through said tubular arm, anelectric circuit, a telephonic receiver, and an amplify.- ing chamberinto which said receiver discharges, and means thereon for deflectingthe amplified sound. 2. In a sound reproducing machine, the combinationwith reproducing means adapted to produce primary vibrations from arecord tablet, and a conduit for such vibrations, of a telephoniccircuit whose transmitter is mounted on said conduit and out of contactwith the sound box and stylus of the reproducer, and whose diaphragm isactuated solely by said primary vibrations, an amplifying chamber intowhich said conduit discharges the primary vibrations, a secondamplifying chamber operatively communieating with the receiver of thetelephonic circuit, a cabinetfor said amplifying chambers, and'meansthereon for commingling and deflecting the amplified primary andsecondary sound vibrations,

3. In asound reproducing machine, the

combination with means adapted to produce primary vibrations from arecord tablet,'and a conduit for such vibrations, of a telephoniccircuit whose transmitter is mounted on said conduit and out of contactwith the sound box and stylus of the reproducer, and whose by saidprimary vibrations, an am li er into which said conduit dischar es t eprimary vibrations, a second amp ifier operatively com municating withthe receiver of the. telephonic-circuit, a cabinet containing both ofsaid amplifiers, and means mounted on said cabinet and projecting overboth amplifiers for directing the sound waves from said amplifiers in acommon direction. I

4. In a sound reproducing machine, the combination with means to produceprimary vibrations from a record tablet, and a con- .duit'forsuchvibrations, of a telephonic circuit whose transmitter is mounted on saidconduit and out of contact with the sound box and stylus of thereproducer, and whose diaphragm is actuated solely by said primaryvibrations; an am lifier into which said conduit discharges t eprimaryvibra-v tions, a second amplifier operatively communicating withthe receiver of the telephonic circuit,'a containin casing in which saidamplifiers are mou-n'te adjacent to each other, and a hinged lid on saidcabinet adapted to cause a commingling of said primary and secondaryvibrations.

5. 'In a sound reproducing machine, the combination with a reproduceradapted to create primary vibrations from a record tablet, and a tubularmovable conduit on which the reproducer is mounted, of a telephonic,

circuit whose transmitter is mounted on said conduit and out of contactwith the reproducer, and whose diaphragm is actuated solely bysaidpri-mary vibrations, an ampliiier operatively communicating with thereceiver of the telephonic circuit, a resistance switch controlling saidcircuit, and an ad-'.

justably pivoted member cooperating with the resistance switch to varythe volume of the amplified sound.

6,- In -a sound reproducing apparatus, means to reproduce recorded soundvibrations from a rotatable tablet, comprising a sound box and stylus, aconduit for said sound vibrations, amplifying means into and throughwhich said sound vibrations are discharged, a branch conduit from theconduit receiving said sound vibrations, a. microphone connected to said'branch con duit, an electric circuit, a receiver therein, a: soundconduit from the reciver, an amplifying member communicating with thelast mentioned sound conduit, and means to direct and commingle theamplified sound waves issuing from both of said amplifiers.

7. In a sound reproducing apparatus, a reproducer, a conduit for soundvibrations created thereby, said conduit having a P threadedflangedopening, a tele honic circuit whose transmitter is actuatsolelyby said sound vibrations, a perforated plug which is threaded andadapted to register with the threaded opening of said conduit, and atransmitter mounted on the. opposite end of said plu 8. In a sounfreproducing machine, the

combination with sound reproducing means for producing primary soundvibrations from a sound record, a conduit for said primary vibrations, atelephonic circuit includot er chare primary vibrations andsupplementfor producing sound vibrations from a sound record, a conduitfor said primary vibrations, a telephonic circuit including atransmitter communicating with said conduit and adapted to be actuatedby said primary vibratlons', and a receiver for producing secondarysoundvibrations and ar ranged to discharge the same simultaneously with thedischarge of the primary vibrations, the transmitting and dischargingmeans being positioned within the same enclosing cabinet. 7

10. In a sound reproducing machine, the combination with soundreproducing means for producing primary sound vibrations from a soundrecord, said primary vibrations being mechanically reproduced, a conduitfor said primary vibrations, and a telephonic circuit including atransmitter communicating with said conduit and adapted to be actuatedby said primary mechanical vibrations, a receiver for producingsecondary sound vibrations and an amplifier therefor, an amplifier forthe primary vibrations, and means whereby the combined vibrations shallbe discharged from the same integral machine.

11. The combination with a talking machine, of electrical means actuatedby and without substantially detracting from the sound mechanicallyproduced by the operation of said machine from a record thereon, tosubstantially augment to a listener to a reproduction of sound from saidmachine the volume of sound produced by said machine. Y

12. lhe combination with a talking machine, of electrical means mountedtherein and actuated by the sound waves produced during the reproductionof sound by said machine from a record thereon to substantially augmentto a listener the volume of sound emitted from said machine, and means.

1 3. The combination with a talking may chine cabinet and a talkingmachine mounted therein, of electrical means also mounted within saidcabinet and actuated by the sound produced by said machine during themechanical reproduction of sound thereby.

within said cabinet and actuated by the. I

sound produced by said machine during the reproduction of sound thereby,to substantially augment to a listener to said machine the volume ofsound emitted from said machine, and means to vary the extent to whichthe said volume is so augmented.

16. The combination with a talking machine cabinet and a talking machinemounted therein, of-telephonic means arranged to be thrown into and outof operation at will mounted within said cabinet .and when thrown intooperation actuated by the sound produced by said machine during thereproduction of sound thereby, to augment to a listener to thereproduction of sound from said machine the volume of sound emitted bysaid machine.

In witness wherof, I have hereunto setmy- 118.1143. and seal this 15 dayof April, A. D., 19 6.

LEON F. DOUGLASS. [13.8.]

